Abstract Smoking remains high in America?s rural southern population despite rapid declines in other regions of the U.S. in recent decades. While 58.3% of U.S. citizens are covered by comprehensive smoke-free (SF) laws, only 16.7% of citizens living in the East South Central or the South Atlantic regions are protected. Current best practices for SF law advocacy have not been effective in closing the gaps in coverage for rural, southern residents. Meanwhile, adoption of voluntary policies (e.g, tobacco-free schools, public housing, outdoor spaces) have accelerated nationwide. The presence of voluntary policies may increase readiness for SF policy adoption or they may derail SF law adoption in rural municipalities in southern states. Our study is innovative because we will incorporate a political theory, Kingdon?s Multiple Streams framework, to guide SF law adoption research in a region with tobacco use disparities. The Specific Aims are to: 1) determine the differences between rural municipalities with and without SF laws in regard to community readiness, problem indicators (e.g., smoking prevalence), focusing events, and feedback; politics (e.g., consensus building); policy factors (e.g., anticipated constraints); and policy entrepreneurs (e.g., strength of tobacco control), controlling for population size and other demographic factors; 1a) compare the number and type of voluntary smoke- and tobacco-free policies (e.g, % tobacco-free schools, public housing, outdoor spaces) in rural municipalities with and without SF laws; and 2) describe facilitators and barriers in the sociopolitical environment that impact advocacy strategies, the policy window (e.g., the tipping point for policy adoption), and enactment of SF laws in rural municipalities with and without SF laws. We will use a mixed methods, case-control design to conduct telephone and online surveys to assess policy adoption factors with local advocates (N = 150-250) and elected officials (N = 150) from 50 municipalities (cities, towns or villages) (25 cases; 25 controls) nested within four states: Alabama, Kentucky, Mississippi, and South Carolina. Case municipalities will have enacted a SF law within the past 3 years; controls will be matched with cases in each state based on community population size and rurality. Using qualitative methods, we also will conduct in-depth interviews with community leaders, citizen activists, and policymakers in case municipalities with the most recent SF law and their matched controls from each state (two communities per state; 10-15 key informants per community). Participants will be asked to describe factors affecting SF policy adoption and asked to comment on key events that may have contributed to or inhibited policy adoption. A Community Advisory Board consisting of 8 leaders in tobacco control and SF law adoption in rural areas and representing the four southern states will guide all aspects of the study. This study will shift the current research paradigm to a new way of understanding SF law adoption in rural, southern municipalities. Tobacco-related health disparities will continue to lead to poor health outcomes and enormous societal costs in rural southern municipalities until we can advance the science of SF policy adoption.